Walker seems to have the same fighter’s DNA. The skinny kid from Destrehan, La., wasn’t good enough for LSU, so he walked on at Tulane three years ago. He became a regular and finally won the starting safety job this season.

The same dedication has driven him to major in Cell & Molecular Biology. No jock-friendly courses there. Walker plans to be a pharmacist or go to med school.

At least those were his plans. Now, nobody knows.

Walker underwent surgery Sunday to stabilize his spine. He has some feeling in his extremities. As the swelling subsides in the next few days, doctors will find out how severe the nerve damage is.

What happened is not a mystery. Walker was zeroing in on a Tulsa runner. He arrived at the target the same time as a teammate. Walker’s helmet slammed into the helmet of defensive tackle Julius Warmsley.

Walker’s body went limp. Trainers and doctors ran to him. The stadium hushed. Players knelt and prayed. “Help is on the way,” coach Curtis Johnson whispered to Walker.

Back home, a horrified mother and father watched on TV and wondered how quickly they could get to their son. The drama has been performed so many times before.

According to the National Center for Catastrophic Sports Injury Research, 295 high school, college, pro and sandlot football players suffered spinal cord injuries from 1977-2009.

Relatively speaking, guys like Utley and LeGrand were lucky. They were hurt in high-profile games and had financial backstops to deal with the millions of dollars in medical and rehabilitation bills.

Then there are guys like Jared Williams and Diondre Preston. They were paralyzed under dim Friday night lights the past couple of years.

After a few heartfelt fundraisers, there’s not much more people can do. The high schoolers often end up scraping by on Medicaid and maybe get a plaque outside their old stadium.

About the only good news is we’ve come a long way since three college players died from injuries in 1905. Leather helmets have given way to things like the Head Impact Telemetry System, where padded sensors record the hits a player’s skull absorbs.

It’s used primarily to track concussions, though a high school player broke his neck while wearing the system a couple of years ago. Sensors showed his helmet sustained a 114 g-force blow. That was more than 30 times as much force Space Shuttle astronauts endure on takeoff.

But while it’s not 1905 anymore, all the technique and equipment refinements will never change the basic physics of football. When heads in motion collide, bad things happen. Then that all-too-familiar scene plays out.

“The kids love Devon,” Johnson said after the game, “and they love the game of football.”

That’s the equation we all deal with. We love the game, so we accept its collateral damage and move on. That’s better than dwelling on the reality.

A kid who wanted to be a doctor lies in an intensive care unit. He doesn’t know if he’ll ever move again. It’s a hell of a price to pay for business as usual.